Completely wrong input capture calculations

int main(void)
{
    Init_Timer3();
    inputcapture_init();
    while(1);
}
void Init_Timer3(void)
{
 IFS0bits.T3IF		= 0;		
 IEC0bits.T3IE		= 1;		
 T3CONbits.TON		= 1;		
 T3CONbits.TCKPS    = 1;      
}

void inputcapture_init(void)
{ 
 ANSELCbits.ANSC0=0;
 _TRISC0=1;
 RPINR7 = 0x30; // MAP_TO_RP48; 
 IC1CON1bits.ICM = 3; /* every rising edge */
 IC1CON1bits.ICI = 0; /* every capture event */
 IC1CON1bits.ICTSEL = 0; /*TIMER3_IC1;*/
 IFS0bits.IC1IF = 0; //RESET_IC1_STATUS_FLAG;	 		// Clear Input Capture1 Flag request
 IEC0bits.IC1IE = 1;//ENABLE_IC1_INTERRUPT;		// Enable Input Capture1 Interrupt request
}

void __attribute__((__interrupt__,__no_auto_psv__)) _IC1Interrupt(void)
{
    previous_capturedata= present_capturedata; /*copy the present value to previous value */
    present_capturedata = IC1BUF; /*Load the register value */
    if(timer3overflowcounter > 0)
   {
     period =   (65535 - previous_capturedata) + present_capturedata + (timer3overflowcounter -1)*65535;
   }
   else
   {
      if(present_capturedata > previous_capturedata)
      {
         period = present_capturedata -  previous_capturedata; 
      }
      else if(present_capturedata < previous_capturedata)
      {
        period = 65535 -  previous_capturedata + present_capturedata;
      }
   }
    timer3overflowcounter=0;
    IFS0bits.IC1IF=0;
}

void __attribute__ ((__interrupt__, no_auto_psv)) _T3Interrupt(void)
{
   timer3overflowcounter++;
    IFS0bits.T3IF = 0;    
}

void __attribute__((__interrupt__,__no_auto_psv__)) _IC1Interrupt(void)
{
g_interrupt_Count++;					//Number Input Capture counts
if(g_interrupt_Count == 1)
{
    g_timer_first_edge_u16 = IC1BUF;
    g_timer3overflowcounter_u8=0;
}
else if(g_interrupt_Count == 2)
{
 g_timer_second_edge_u16  = IC1BUF;
 if(g_timer3overflowcounter_u8 < 2)
 {
  g_period_u16 = g_timer_second_edge_u16 - g_timer_first_edge_u16;
 }
 g_interrupt_Count=0;
}		
  IFS0bits.IC1IF=0;
}

void Init_Timer3(void)
{
 IFS0bits.T3IF		= 0;		
 IEC0bits.T3IE		= 1;	
 T3CONbits.TCKPS    = 1;  
 T3CONbits.TON		= 1;		
}

void __attribute__ ((__interrupt__, no_auto_psv)) _T3Interrupt(void)
{
    g_timer3overflowcounter_u8++;
    IFS0bits.T3IF = 0;    
}